ECM error codes? How do you retrieve the codes?
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Melting Slicks
Joined: Aug 2001
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From: Fishkill NY
ECM error codes? How do you retrieve the codes?
Is there an inexpensive way to read the ECM codes? I have the list of all the error codes but, I know they sell a unit call Diacom (pc based) for about $275 and another one hand held for about $175. Is there cheep way to read the codes? :smash:
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Re: ECM error codes? How do you retrieve the codes? (1991C4)
cheapest way? A paper clip on the A and B terminals of the ALDL connector under the dash.
Jumper terminals A and B, turn the key on, do not start car.
Check Engine light will flash each code three times before moving on to the next. It will start with 12 which means nothing..... then it will move on to the next code.
Example. Jumper terminals. Turn key on. Check engine light will flash like this:
Flash ---- flash - flash -------------flash -----flash -flash ---------------flash -----flash - flash
That would be for "1-2-------1-2------1-2-----" Get it?
Then to the next code.... say it's 32:
flash - flash -flash --------flash - flash ----------------------flash - flash -flash-----flash - flash ------------flash - flash -flash --------flash - flash
that's '3-2------3-2-------3-2-------'
It will cycle through all codes and then start back at 12 again.
[Modified by Marcho Polo, 5:39 PM 8/30/2001]
Jumper terminals A and B, turn the key on, do not start car.
Check Engine light will flash each code three times before moving on to the next. It will start with 12 which means nothing..... then it will move on to the next code.
Example. Jumper terminals. Turn key on. Check engine light will flash like this:
Flash ---- flash - flash -------------flash -----flash -flash ---------------flash -----flash - flash
That would be for "1-2-------1-2------1-2-----" Get it?
Then to the next code.... say it's 32:
flash - flash -flash --------flash - flash ----------------------flash - flash -flash-----flash - flash ------------flash - flash -flash --------flash - flash
that's '3-2------3-2-------3-2-------'
It will cycle through all codes and then start back at 12 again.
[Modified by Marcho Polo, 5:39 PM 8/30/2001]
Thread Starter
Melting Slicks
Joined: Aug 2001
Posts: 2,753
Likes: 1
From: Fishkill NY
Re: ECM error codes? How do you retrieve the codes? (Marcho Polo)
That sounds to easy! I have heard of this some time back. To bad there is not a reader that would just plug in and show the code for cheep. I know some of the others do much more but when your tying to find out what is wrong, most times all you want is a reader. Thanks
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Joined: Mar 1999
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From: At the beach in little Rhody
Re: ECM error codes? How do you retrieve the codes? (1991C4)
I have seen readers, but in the end I don't think they are worth the money. The paper clip routine can be used not only for ECM diagnostics, but also your ABS and CCM. As far as diagnostics go, I have a Auto X-Ray that I use, but I use it more for retrieving run data then codes. Even though I have the Auto X-Ray, I usually just jump the pins and count flashes for the error codes.
